[Screening and healthcare for pregnant women with psycho-social vulnerability : A French national study]. / Dépistage et parcours de soins en cas de vulnérabilités psycho-sociales maternelles : une enquête nationale française.

INTRODUCTION: Psycho-social vulnerabilities are a medical risk factor for both fetus and mother. Association between socioeconomic status and prenatal follow-up has been well established and inadequate follow-up is associated with higher morbidity and mortality in women in unfavorable situations. OBJECTIVE: The objective is to identify screening strategies and to describe existing systems for pregnant women in psycho-social vulnerability in French maternity hospitals. MATERIAL AND METHODES: This is a national survey conducted by questionnaire in all French maternities. RESULTS: Screening by means of targeted questions is carried out by 96.7% of maternity units. Early prenatal interviews are offered systematically by 64% of maternity units and access to them is still difficult for women in vulnerable situations. In order to organize care pathways, 28.7% of maternities have a structured unit within their establishment and 81% state that they have mobilizable caregivers. Multidisciplinary meetings for the coordination of the various stakeholders are held by 85.8% of maternity units. Collaboration with networks and associations is emphasized. CONCLUSION: A large proportion of maternities seek to identify women in situation of psycho-social vulnerabilities and to organize care paths. However, the resources implemented still appear insufficient for many maternity units. Each maternity hospital has resources and is developing initiatives to deal with the difficulties of care.

Screening for active and latent TB among migrants in France.

SETTING: Migrants to Europe face a disproportionate burden of infections, including TB, yet little is known about the approach taken by primary and secondary care providers to screening and treatment. We therefore explored policy and practice relating to screening of active TB and latent TB infection (LTBI) in France.METHODS: We conducted an online national survey of French primary and secondary care physicians regarding their practices in relation to TB/LTBI screening among migrants.RESULTS: 367 physicians responded to the questionnaire among which 195 (53.1%) were primary care physicians, 126 (34.3%) were TB specialists in secondary care, and 46 (12.5%) other physicians; 303 (85.5%) were involved daily in the care of migrants. Most respondents recommended systematic TB screening with chest X-ray for migrants from medium and high-incidence countries (71.9%). Primary care physicians were less likely to offer screening than physicians in other settings (aOR 0.21, 95% CI 0.09-0.48). 220 (61.8%) offered LTBI screening for children (<15 years) and 34.0% for all migrants from high incidence countries.CONCLUSION: Improving awareness on TB screening is a critical next step to improve health outcomes in migrant groups and meet regional targets for tackling TB.

Estudios del laboratorio de diversos parámetros orientados a tratar de dilucidar la fisiopatología del síndrome de ovarios poliquísticos (SOP). Parte 2 / Laboratory studies of several parameters aimed to elucidate the pathophysiology of polycystic ovary syndrome. Second part

RESUMEN Diversos estudios bioquímicos adicionales a la evaluación de Testosterona total (TT), biodisponible (Tbio) y libre (TL) han sido realizados a los efectos que pudieran resultar de mayor utilidad para el diagnóstico de patologías concomitantes en el SOP, entre otros. En la hormona anti Mülleriana, cuando la concentración supera a los 3,0 ng/ml existen evidencias de que el 79% de las mismas pueden ser identificadas correctamente como SOP. El Antígeno Prostático Específico (PSA), marcador de singular importancia en pacientes con cáncer de Próstata, con técnicas ultrasensibles ha podido ser detectado en más del 50% en mujeres. En un grupo de pacientes con SOP, los niveles circulantes de PSA fueron significativamente mayores que en las mujeres sin SOP. El Kiss-1 aislado de la placenta y demostrado en otros tejidos, presenta niveles aumentados que correlacionan con la LH, TT, TL y resistencia a la insulina (RI) en adolescentes con SOP versus adolescentes sin SOP, sugiriendo que el Kiss-1 podría estar involucrado en el desarrollo del SOP en estas pacientes. Algunas pacientes con SOP están asociadas a patologías relevantes, de las cuales han sido comunicadas el aumento del BMI, mayor grado de dislipemia, adiposidad central, RI y Síndrome Metabólico (SMe). En las pacientes con un fenotipo clásico (hiperandrogenismo, alteración del ciclo menstrual y ovarios poliquísticos), estas patologías son de mayor frecuencia y severidad que en los otros fenotipos, particularmente aquellos sin hiperandrogenismo. Otras determinaciones como TNFα, interleuquinas, test de tolerancia a la glucosa, ApoB, partículas pequeñas de LDL e Inhibidor del Activador del Plasminógeno-1 han sido comunicados que podrían ser de utilidad para tener mayor sensibilidad en la definición de patología concomitantes en el SOP. Actualmente se ha comenzado a evaluar otros marcadores como el Fetuin-A; Quemerina, Nesfatina-1, Neopterina y Endocannabinoides, cuyos resultados preliminares parecerían ser un aporte importante para evaluar SMe y RI en paciente con SOP y tratar de definir su prevalencia en los distintos fenotipos de esta patología.

ABSTRACT Several biochemical studies in addition to the evaluation of total Testosterone (TT), bioavailable (bioT) and free (FT) have been performed to the effects that could be of greater use for the diagnosis of concomitant pathologies in the PCOS, among others. The anti-Müllerian hormone whose concentration when exceeds 3.0 ng/ml, there is evidence that 79% of these patients can be correctly identified as PCOS. The Prostate-Specific Antigen (PSA), a marker of singular importance in patients with prostate cancer, with ultra-sensitive techniques, has been detected in more than 50% of women. In a group of patients with PCOS, circulating levels of PSA are significantly higher than in women without PCOS. The Kiss-1 isolated from the placenta and demonstrated in other tissues, has increased levels that correlate with LH, TT, TL and insulin resistance (IR) in adolescents with PCOS respect to adolescents without PCOS, suggesting that Kiss-1 could be involved in the development of the PCOS in these patients. In some patients with PCOS, they are associated with relevant pathologies, of which the increase in BMI, higher degree of dyslipidemia, central adiposity, IR and Metabolic Syndrome (MeS) have been reported. Those that show a classic phenotype (hyperandrogenism, alteration of the menstrual cycle and polycystic ovaries) these characteristics are of greater frequency and severity than in the other phenotypes, particularly those without hyperandrogenism. Other determinations such as TNFα, interleukins, glucose tolerance test, ApoB, small particles of LDL and Plasminogen Activator Inhibitor-1 have been reported that could be useful to have greater sensitivity in the definition of concomitant pathology in the PCOS. Currently, other markers such as Fetuin-A, Chemerin, Nesfatin-1 Neopterin and Endocannabinoids have been evaluated. The preliminary results suggest to be an important contribution to define MeS and IR in patient with PCOS and to try to determine its prevalence in the different phenotypes of this pathology.

Estudios de laboratorio de diversos parámetros orientados a tratar de dilucidar la fisiopatología del síndrome de ovarios poliquísticos. Parte 1 / Laboratory studies of various parameters aimed at trying to elucidate the pathophysiology of polycystic ovary syndrome. Part 1

Esta revisión fue realizada con el fin de evaluar nuestros resultados de laboratorio así como aquellos de la literatura que constituyen, a nuestro entender, aportes significativos en el síndrome de ovarios poliquísticos (SOP). Nuestro especial énfasis será presentar las limitaciones de las metodologías empleadas por nuestro grupo, comparativamente a las reportadas por otros investigadores. La determinación de andrógenos, en particular de Testosterona (TT), es quizá la de mayor complejidad dado que los resultados con los diferentes inmunoensayos empleados en nuestro medio producen resultados muy variables por los diferentes métodos y aún entre laboratorios que usan la misma metodología. La técnica de referencia es la cromatografía líquida en tándem con espectrometría de masa (LC-MSMS), de difícil aplicación en laboratorios de análisis clínicos debido a su alto costo y la imposibilidad de resolver numerosas muestras. En estudios previos demostramos que de los métodos habitualmente usados para evaluar la TT circulante, solo en 2 inmunoensayos los resultados obtenidos fueron satisfactoriamente validados indirectamente según el criterio del Consenso de los Centros para el Control y Prevención de Enfermedades (CDC, USA) contra LC-MSMS, los cuales fueron comparables a dicha metodología con niveles superiores a 0,5 ng/ml. El SOP puede presentar factores de riesgo aumentados para la enfermedad cardiovascular y la diabetes II. Estos factores no están debidamente categorizados en función de los distintos fenotipos del SOP. Se evaluarán los principales analitos empleados con este objetivo y los nuevos que aporten elementos de mayor especificidad en este sentido

This review was performed in order to evaluate our laboratory results as well as those of the literature that constitute, in our opinion, significant contributions in these pathophysiologies. Our special emphasis will be on presenting the limitations of the methodologies used by our group, compared to those reported by other researchers. The determination of androgens, in particular Testosterone (TT), is perhaps the most complex since the results with the different immunoassays used in our environment produce very variable results by the different methods and even between laboratories that use the same methodology. The reference technique is LC-MSMS, difficult to apply in clinical analysis laboratories because of its high cost and the inability to solve numerous samples. In previous studies, we demonstrated that, in comparison to LC-MSMS with the usual methods for evaluating circulating TT, the results obtained in only 2 immunoassays were satisfactorily validated indirectly according to the criteria of CDC against LC-MSMS, which were comparable to that methodology with levels higher than 0.5 ng/ml. PCOS may have increased risk factors for cardiovascular disease and diabetes II. These factors are not properly categorized according to the different phenotypes of PCOS. The main analytes used for this purpose will be evaluated and new ones that contribute elements of greater specificity in this sense

Factores que afectan al ambiente educativo en la formación preclínica de medicina según sus docentes / Factors affecting the educational environment in undergraduate medical schools

Background: Educational environment has an important effect on the quality of learning and student satisfaction in medicine. Most of previous studies have been conducted using questionnaires that assess the phenomenon considering overall dimensions, without paying attention to the specific manifestations of this topic, especially those aspects that are related to the protagonists of the learning process: teachers and students. Aim: To describe factors that affect the educational environment in the preclinical Medical formation, according to Medical teachers in Concepción, Chile. Material and Methods: Qualitative study, using the Grounded theory method. Semi-structured interviews were performed to 10 medical teachers in Concepcion, Chile. They were selected by theoretical sampling. Data were analyzed using open coding. Results: Four emerging categories about the factors that affect the learning environment were identified: Personal factors of students, academic factors of students, personal factors of teachers and academic factors of teachers. Conclusions: According to interviewed teachers, both personal factors in teachers and students that promote a positive learning environment are related with an attitude oriented towards others and communication skills. Academic factors are related with the responsible exercise of student and teacher roles and with the promotion of participation in the educational process.

Aspectos motivacionales involucrados en el aprendizaje autodirigido en estudiantes de medicina. un enfoque cualitativo / Motivation and self-directed learning among medical students

Background: Motivation is an essential aspect in the training process of medical students. The association that motivation can have with learning self-regulation is of utmost importance for the design of curriculum, teaching methods and evaluation. Aim: To describe the motivational aspects of self-directed learning among medical students from a traditional Chilean University. Material and Methods: A qualitative, descriptive study based on grounded theory of Strauss and Corbin. Twenty 4th and 5th year medical students were selected using a maximum variation sampling technique. After obtaining an informed consent, semi-structured interviews and field notes were carried out. Data were analyzed to the level of open coding through Atlas-ti 7.5.2. Results: From the student point of view, personal motivational aspects are linked to the search for information, constant updating, the perception of the physician-patient relationship and interest in subject matters. From the scope of teachers, a main issue is related to their ability to motivate students to develop independent study skills. Conclusions: Personal motivational aspects facilitate the development of independent study skills, specifically in the search of information. The role of teachers is crucial in promoting these skills and the perception of medical students from their learning process.

A Comparison of Serum Testosterone (T) Measurements by Various Methods, Employing Current Validated Techniques or Otherwise, and Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS): A Multicentric Study / Comparación de los resultados de testosterona (T) por cromatografía líquida en tandem con espectrometría de masa (LC-MS/MS) y por kits comerciales convalidados o no por LC-MS/MS

Objective: To compare normal and hirsute women Testosterone (T) measurements performed at different laboratories by the same or different methods, and the gold standard method LC-MS/MS (Quest Diagnostics, USA). Design: Prospective study. Setting: Hormone Determination Laboratory, Hospital Italiano, La Plata, and each participating laboratory's private practice. Patient(s): Blood samples were obtained from 23 individuals sorted into two groups, namely, normal women, n: 11(NW) and hirsute women, n: 12 (HW). Interventions(s): None. Main Outcome Measure(s): To evaluate whether serum T measurements obtained from each serum by the methods currently employed in our country, some of whose kits exhibit changes in previous presentations, some LC-MS/MS-validated and other non-validated ones are significantly different from those obtained by LC-MS/MS. Result(s): None of the 11 NW showed high T values by LC-MS/MS. Two out of the 12 hirsute patients showed normal T values (LC-MS/MS). Methods and number of participating labs -shown between brackets were: in NW, 1st generation Architect (1), 2nd generation Architect (1); Immulite (1) Cobas (4); Access (1); Centaur (2); Immunotech-RIA (1); and, in HW, 2nd generation Architect (3); Immulite (3); Cobas (4); Access (1); Centaur (2); Immunotech-RIA (1). No false positives resulted from the assays performed. No lab yielded false positive results in the NW group. No false positives were reported from the 10 hirsute women with increased T values by LC-MS/MS. False positives, though, resulted from two female hirsute patients with normal T values studied by four of the methods. Statistically, the serum T measurements obtained were significantly different by Centaur in NW and, in HW, by Immulite and Centaur as compared to LC-MS/MS. In the Bland-Altman plot, Centaur and Cobas showed over 5 % of measurements outside the limits of agreement in the HW group. Assessment by p-Spearman resulted in divergences with LC-MS/MS for all methods in NW, whereas in the HW group there were none. When estimating sampling bias for each laboratory taking LC-MS/MS as the reference method and adopting a ± 6.4 % mean bias acceptability criterion for each method compared to LC-MS/MS, two of the techniques reviewed, 2nd generation Architect and Cobas, met the validation requirement satisfactorily. However, one lab out of three using 2nd generation Architect failed to meet the validation requirement, while two out of four labs using Cobas also failed to meet the requirement. This demonstrates the great variability among methods, even when labs are employing the same technique. Conclusion: From the clinical point of view, the methods currently used in our local environment yielded no false positives or false negatives and therefore did not misdiagnose hyperandrogenism. Still, Immulite, Centaur, RIA and Access did present false positives in two of the T-normal hirsute women. The relation of serum T measurements obtained by each method to measurements obtained by LC-MS/MS reveals that the dispersion of the results was larger with values under 0.3 ng/ml, quite close to the detection limit of the various techniques.

Objetivos: Comparar los resultados de testosterona (T) obtenidos en diferentes laboratorios en mujeres normales (MN) e hirsutas (MH), empleando el mismo o diferentes métodos respecto a la técnica de cromatografía líquida en tándem con espectrometría de masa LC-MS/MS (gold standard) realizada en el laboratorio Quest (USA) Protocolo: Estudio prospectivo Estudio realizado en: Laboratorio de Determinaciones Hormonales; Hospital Italiano de La Plata y en los laboratorios privados de cada participante Pacientes: Se obtuvieron muestras de sangre periférica en 23 mujeres agrupadas en 2 grupos: controles normales (n:11) y en mujeres hirsutas (n: 12) Intervención: Ninguna. Principales resultados a evaluar: Evaluar si con los métodos habituales empleados en nuestro medio con los diferentes kits comerciales, de los cuales algunos han sido convalidados por técnica "gold standard" y otros no, presentan diferencias significativas con los obtenidos por LC-MS/MS Resultados: Los resultados obtenidos por LC-MS/MS mostraron que ninguna de las 11 MN tuvieron niveles aumentado de T y 2 MH tuvieron valores normales de T. Los métodos empleados y el número de laboratorios (entre paréntesis) que emplearon cada método fueron en MN Architect 1st generation (1) Architect 2nd generation (1); Immulite (1); Cobas (4); Access (1); Centauro (2); Immunotech-RIA (1). En las MH Architect 2nd generation (3); Immulite (3); Cobas (4); Access (1); Centauro (2); Immunotech-RIA (1). En el grupo de MN en ningún laboratorio (lab) se obtuvieron resultados falsos positivos. En el grupo de MH no se obtuvieron falsos negativos en las 10 hirsutas con valores aumentados de T por LC-MS/MS. En las 2 pacientes hirsutas con T normal en 4 métodos se obtuvieron falsos positivos Estadísticamente los resultados fueron significativamente diferentes, en las MN por Centauro y en las MH por Immulite y Centauro. En el análisis de Bland-Altman Centauro y Cobas en las MH presentaron más del 5 % de los resultados fuera del límite de acuerdo. Resultados por p-Speerman todos los métodos fueron diferentes a LC-MSMS en las MN y no se obtuvieron diferencias en el grupo de MH. Evaluando el bias de cada muestra en cada laboratorio respecto a LC-MS/MS y adoptando el criterio de aceptabilidad de ± 6,4 % mean bias de cada método respecto al de LC-MS/MS, 2 de las metodologías estudiadas, Architect 2da generación y Cobas pasaron satisfactoriamente el requisito de validación, sin embargo de los 3 laboratorios que emplearon 2da generación, 1 no pasó el criterio de validación y de los 4 que usaron Cobas, 2 tampoco lo pasaron. Esto demuestra la gran variabilidad de los métodos aun entre lab que emplean la misma técnica. Conclusiones: Desde el punto de vista clínico los métodos habitualmente empleados en nuestro medio, no sobrediagnosticaron o subdiagnosticaron hiperandrogenismo, por no presentar falsos positivos o negativos respectivamente. Sin embargo Immulite, Centauro, RIA y Access presentaron falsos positivos en las 2 hirsutas con T normal. En la relación de los resultados de cada muestra en cada método sobre el valor de LC-MS/MS referido a la concentración de T en ese suero por LC-MS/MS, la mayor dispersión de los resultados se observaron con valores menores de 0,3 ng/ml, muy cercano al límite de detección de las diferentes técnicas.

Predictores afectivos y académicos del aprendizaje autodirigido en estudiantes de medicina / Factors associated with self-directed learning among medical students

Background: Self-directed learning is a skill that must be taught and evaluated in future physicians. Aim: To analyze the association between self-directed learning, self-esteem, self-efficacy, time management and academic commitment among medical students. Material and methods: The self-directed learning, Rosemberg self-esteem, general self- efficacy, time management and Utrecht work engagement scales were applied to 297 first year medical students. Results: A multiple regression analysis showed a significant association between self-efficacy, time management and academic commitment with self-directed learning. Self-esteem and satisfaction with studies did not enter in the model. Conclusions: self-esteem, academic commitment and a good time management were associated with self-directed learning in these students.

Aprendizaje autodirigido y su relación con estilos y estrategias de aprendizaje en estudiantes de medicina / Relationship between self-directed learning with learning styles and strategies in medical students

Background: Self-directed learning (SDL) skills are particularly important in medical education, considering that physicians should be able to regulate their own learning experiences. Aim: To evaluate the relationship between learning styles and strategies and self-directed learning in medical students. Material and Methods: One hundred ninety nine first year medical students (120 males) participated in the study. Preparation for Independent Learning (EPAI) scale was used to assess self-direction. Schmeck learning strategies scale and Honey and Alonso (CHAEA) scales were used to evaluate learning styles and strategies. Results: Theoretical learning style and deep processing learning strategy had positive correlations with self-direct learning. Conclusions: Medical students with theoretical styles and low retention of facts are those with greater ability to self-direct their learning. Further studies are required to determine the relationship between learning styles and strategies with SDL in medical students. The acquired knowledge will allow the adjustment of teaching strategies to encourage SDL.

Evaluación de componentes del currículum oculto en estudiantes de medicina / Assessment of hidden curriculum components by medical students

Background: Hidden curriculum refers to the unwritten, unofficial, and often unintended lessons, values, and perspectives that students learn at the university, which influences the acquisition of professional skills. Aim: To analyze the perception about the influence of the hidden curriculum in the education of medical students at the Universidad de Concepción, Chile. Material and Methods: Qualitative investigation with case study approach. Seventeen graduated medical students were selected by probability sampling. A semi-structured interview was used to collect the information and a content analysis was applied. Results: Forty seven percent of participants recognized having fulfilled their academic expectations. As favorable factors for academic achievement the students underlined clinical practice, access to patients and to clinical fields. As negative factors, they identified the lack of commitment, educational support and over-specialization of their mentors. Conclusions: The results show the strengths and weaknesses of the educational environment of undergraduated medical students. This information should be used to modify teaching environments.

Paratiroidectomía en pacientes renales crónicos en Argentina: estudios prequirúrgicos, tipos de cirugía, recurrencia y persistencia / Parathyroidectomy in chronic kidney disease patients in Argentina: pre surgical studies, types of surgery, recurrence and persistence

La paratiroidectomía (PTx) es el tratamiento de elección en pacientes con HPT 2º severo, refractario al tratamiento médico. Se cuenta con muy poca información en Argentina de este procedimiento, por lo cual se realizó este estudio. Material y Métodos: Se incluyeron 255 pacientes con PTx entre el año 2003 al 2007 de un registro voluntario. Se evaluaron los estudios de localización prequirúrgicos, de laboratorio de metabolismo fosfocálcico previo y posterior a la cirugía y el tipo de técnica quirúrgica utilizada. Se analizó la persistencia y recidiva del HPT postcirugía. Resultados: La tasa de PTx fue de 2,7/1000 pacientes año. 83% de los pacientes tuvieron ecografía de cuello y 59% Sesta Mibi con Tc 99. Hubo una correlación positiva (p<0.001) entre el número de glándulas detectadas por ecografía y Sesta Mibi. La paratiroidectomía realizada fue: subtotal en 77%, total con autoimplante en 14% y total sin autoimplante en 9%. Hubo descensos significativos de Ca y P, fosfatasa alcalina y PTH (1744 ± 788 pg/ml a 247 ±450 pg/ml; p<0.0001) postcirugía. A los 2,4 ±2,5 meses de la PTx, el 72% de los pacientes tenía PTH <250 pg/ml, 19,8% tenía persistencia y 8,3% había recidivado. De acuerdo al tipo de cirugía la persistencia y recidiva fueron para PTx subtotal 22% y 8,3%, PTx total con implante 11% y 11% y PTx total sin autoimplante 13% y 4% respectivamente. La realización de Sesta Mibi no influyó en los resultados de la PTx. No se observaron diferencias entre los centros en relación con persistencia y recidiva. Conclusiones: La tasa de PTx fue muy baja, la ecografía fue el método de localización prequirúrgico preferido y la PTX subtotal la técnica quirúrgica más utilizada. La PTx fue exitosa en la mayoría de los pacientes y la persistencia y recidiva no estuvieron relacionadas con la técnica.

Parathyroidectomy (PTx) is the selecte treatment for patients with severe secondary hyperparathyroidism, refractory to medical treatment. There is not enough information about this procedure in Argentina, that is the reason why we performed this study. Material and Methods: 255 patients with PTx were included from the year 2003 to 2007 on a voluntary register. Studies of pre-surgical localization, phosphocalcic metabolism laboratories before and after surgery were evaluated, and the type of surgical technique used. The persistence and recurrence of post-surgical hyperparathyroidism was analyzed. Results: The PTx rate was 2,7/1000 patients year. 83% of the patients had neck echography and 59% Sestamibi scans with Tc 99. There was a positive correlation (p<0,001) between the number of detected glands by echography and Sestamibi. The parathyroidectomy performed was: subtotal in 77%, total with self-implant in 14% and total without self-implant in 9%. There were significant falls of Ca and P, Alkaline Phosphatase and PTH (1744±788 pg/ml to 247±450 pg/ml; p<0.0001) post-surgical. 2.4 ±2,5 months after the PTx, 72% of patients had PTH <250 pg/ml, 19,8% had persistence and 8,3% had recurrence. According to the type of surgery, the persistence and recurrence were for subtotal PTx 22% and 8,3%, total PTx with implant 11% and 11%, and total PTx without selfimplant 13% and 4% respectively. The performance of the Sestamibi scan did not affect the PTx results. No noticeable differences were observed among the centers for persistence and recurrence. Conclusions: The PTx rate was very low, echography was the preferred method of pre-surgical localization, and subtotal PTx was the most used surgical technique. PTx was successful in most of the patients, and persistence and recurrence were not related to the technique.

Endoscopic third ventriculostomy: can we predict success during surgery?

Endoscopic third ventriculostomy (ETV) is widely used as an alternative technique for hydrocephalus treatment. ETV success or failure may be influenced by numerous factors. In this study, we have analyzed preoperative and intraoperative risk factors and suggest an intraoperative scale to predict etV failure. Fifty-one patients (27 adults and 24 children) underwent an etV at Carlos Haya University Hospital, Malaga. Intraoperative video records were assessed and the following intraoperative findings were recorded: (1) abnormal ventricular anatomy, (2) intraoperative incident, (3) Liliequist membrane opening in a second endoscopic maneuver, (4) thickened or scarred membranes in the subarachnoid space, (5) absence or "weakness" of pulsation of third ventricle floor at etV completion, and (6) floppy premammillary membrane that needs edge coagulation. An intraoperative scale ranging from 0 to 6 points was performed. A significant relation was found between a higher result on the prognosis scale and etV failure (p < 0.0001). An absence or weakness of pulsation of the third ventricle floor at etV completion was significantly related to etV failure (p < 0.0001). The presence of thickened or scarred membranes in the subarachnoid space was significantly related to etV failure (p < 0.04) as well as the Liliequist membrane opening in a second endoscopic maneuver (p < 0.008). Intraoperative factors should be taken into account for prediction of etV success. More studies with larger case series are needed to determine the influence of all intraoperative factors over etV success.

Quantification of Testosterone (T) by 8 Immunoassays and by Liquid Chromatography -Tandem Mass Spectrometry (LC-MSMS) in Normal and Hirsute Women: A Multicenter Study / Cuantificación de testosterona (T) por 8 inmunoensayos y por cromatografía líquida en tandem con espectrometría de masa (LC MS/MS): En mujeres normales e hirsutas. Estudio multicéntrico

Objective: To compare T results in normal and hirsute women, obtained by different laboratories employing the same or different methods, including an in-home RIA, and the gold standard method LC-MS/MS. In addition, T results were referred to a curve obtained by 6 different pools that had been prepared on the basis of LC-MS/MS results. Design: Prospective study Setting: Hormone Determination Laboratory, Hospital Italiano, La Plata, and private practice of each participant laboratory. Patient(s): Blood samples were obtained from 78 individuals sorted into 3 groups, namely, normal men (n:39), normal women (n:24) and hirsute women (n:15) Interventions(s): None Main Outcome Measure(s): To evaluate if the results obtained in each lab for each serum sample by the methods currently employed in our country are significantly different from those obtained by LC-MS/MS (Gold standard) Result(s) One out of the 24 NW showed high T values by LC - MS/MS. In each lab, except in 1 (Architect) T results of this serum sample were normal. Two out of the 15 hirsute patients showed normal T values (LC - MS/MS). Method and number of labs -shown between brackets- and percentages of normal T results (false negatives) are described for each method as follows: Chemiluminescence: Axsym - Abbott (Axn) - (3) 85, Architect - Abbott - (Arch); (2) 70; Immulite - Siemmens - (IMM); (2) 42; Electrochemiluminescence - Elecsys - Roche- ((EQL); (4) 52; Fluorescent enzymatic - Vidas - Bio-Merieux - (Vidas) (1) 69; Manual coated tube radioimmunoassay (RIA): RIA - Siemmens Coat-a-Count (RIA S); (3) 64; RIA - DSL Inc (RIA DSL); (1) 31; RIA - DIASource - (DiaS); (1) 31; and in-Home RIA (in-H) (1) 12. Statistically significant differences were obtained between different methods and against LC MS/MS. In-H method is the one that comes closest to 1 on the Weighted Deming regression and closest to zero on the SD intercept, (standard deviation of the constant in the straight line equation) indicating that the values match those obtained by LC - MS/MS. The values recorded by the various methods employed showed no significant modifications when plotted against a secondary standard curve. Conclusion(s) This indicates that the techniques in current use in our area underestimate hyperandrogenemia in these patients. Discrepancies are not due to the various calibration curves proposed in the corresponding commercial kits. The fact that the In-H technique affords finer results while employing a larger serum volume suggests that the disparities among the various commercial methods result from their limited sensitivity to the sample volumes they process.

El diagnóstico de hiperandrogenemia requiere la demostración de niveles aumentados de Testosterona Total (TT) en suero. Los inmuno ensayos comerciales dan resultados divergentes a niveles bajos de TT como los obtenidos en mujeres. Valoramos los niveles de TT en 24 mujeres normales (MN) y 15 hirsutas (MH) en 18 laboratorios por métodos comúnmente empleados en nuestro medio. Los métodos y número de laboratorio que emplearon cada método se muestra entre paréntesis así como los porcentajes de T normal (falsos negativos) obtenidos en cada método fueron: Quimioluminiscencia: Axsym - Abbott (Axn)- (3) (85), Architect - Abbott - (Arch); (2) 70; Immulite - Siemmens - (IMM); (2) 42; Electroquimioluminiscencia - Elecsys - Roche- ((EQL); (4) 52; Enzimático acoplado a fluorescencia Vidas - Bio-Merieux - (Vidas) (1) 69, Radioinmunoiensayo en tubo recubierto (RIA): RIA - Siemmens (RIA S); (3) 64; RIA - DSL Inc (RIA DSL); (1) 31; RIA - DIASource - (DiaS); (1) 31; y un método desarrollado en uno de los laboratorios (in-H) (1) 12. Comparativamente a LC MS/MS los niveles fueron en todas las muestras significativamente más bajos por Axn y en 18 de las 24 MN por DiaS. En 7 casos; 3 por RIA S, 2 por IMM y 1 por EQL y Arch los valores de TT fueron superiores al límite superior de sus respectivos métodos. En todos los casos se obtuvo una gran variación entre los mismos y con diferentes métodos. Trece de las 15 MH tuvieron niveles altos de TT por LC MS/MS. De las MH con TT aumentada de acuerdo a la determinación por LC MS/MS entre el 12 y el 85 % de las mismas por los distintos métodos fueron normales, indicando que en la mayoría de los métodos habitualmente utilizados en nuestro medio subvaloran la hipernadrogenemia en estas pacientes. Estas diferencias se hacen más notorias a niveles más bajos de TT (Se obtuvieron valores normales en el 71 % de los casos con valores de TT entre 0,47 y 0,74 ng/ml y en el 38 % de los casos, con niveles de TT mayor a 0,98 ng/ml). ...

Invaginación intestinal ileoileal causada por divertículo de Meckel / Ileoileal intussusception due to Meckel's diverticulum

Introducción: La invaginación intestinal constituye la principal causa de obstrucción intestinal en lactantes. En este rango etáreo, la mayoría de los casos son idiopáticos y de localización ileocecal, siendo infrecuentes las invaginaciones ileoileales originadas por una alteración anatómica del tracto gastrointestinal como el Divertículo de Meckel. Objetivo: Presentar 2 casos de invaginación intestinal ileoileal en lactantes causadas por Divertículo de Meckel. Casos clínicos: El primer caso corresponde a una lactante de sexo femenino de 6 meses que presentó cuadro de dolor abdominal cólico asociado a vómitos y deposiciones sanguinolentas. El segundo, a un lactante de sexo masculino de 1 año y 11 meses con antecedentes de Tetralogía de Fallot operada y Síndrome de Di George que consultó por compromiso del estado general, vómitos y deshidratación severa, asociándose en los días siguientes deposiciones semilíquidas no sanguinolentas. Conclusiones: La invaginación intestinal ileoileal es infrecuente, en especial las causadas por alteraciones anatómicas como el Divertículo de Meckel en lactantes. Esta asociación no tiene signos patognomónicos y su estudio no difiere del habitual de intususcepción intestinal, pero es importante considerarla para el manejo, pues posee indicación quirúrgica y está contraindicada la reducción neumática.

Introduction: Intussusception is the most common cause of intestinal obstruction in infants. At this age, most cases are idiopathic and involve ileocecal locations; meanwhile ileoileal invaginations caused by an anatomic abnormality of the gastrointestinal tract, such as Meckel's diverticulum, are rare. Objective: To report two cases of infant ileoileal intussusception due to Meckel's diverticulum. Case reports: The first patient was a 6 month-old female infant who presented colicky abdominal pain associated with vomiting and bloody stools. The second patient, a 23 month-old male infant with a history of Tetralogy of Fallot and corrective surgery, and DiGeorge syndrome, who consulted the specialists for health worsened due to vomits and severe dehydration, presenting the following days, semi-liquid and non-bloody stools. Conclusions: Ileoileal intussusception is rare in infants, especially those caused by anatomical changes such as Meckel's diverticulum. This association has no pathognomonic signs and its study does not differ from the usual study of intestinal intussusception, but it is important to consider it for management purposes as it involves surgical intervention and considering that the pneumatic reduction is contraindicated.

Teratoma sacrococcígeo: reporte de un caso, desde el diagnóstico antenatal a la resección y reconstrucción primaria / Sacrococcygeal teratoma: case report, from prenatal diagnosis to resection and primary reconstruction

INTRODUCCIÓN: Los teratomas sacrococcígeos (TSC) constituyen una patología infrecuente en la edad pediátrica (1/27.000 recién nacidos vivos), aunque es la neoplasia más frecuente de diagnóstico fetal. La disponibilidad ecográfica ha permitido el diagnóstico antenatal de muchas de estas lesiones, lográndose planificación oportuna, estudio y tratamiento multidisciplinario de estos pacientes. PRESENTACIÓN DEL CASO: Al control ecográfico prenatal, el paciente presenta masa quística heterogénea en polo caudal, decidiéndose cesárea electiva al término por sospecha de TSC. Nace en buenas condiciones destacando masa sacrococcígea de 15 cm de diámetro. Las imágenes son compatibles con TSC Altman II. Luego de completado el estudio con marcadores tumorales, se opera al 9º día de vida extirpándose el tumor y cóccix en su totalidad, se reconstruye el piso pelviano y se logra cierre primario. El paciente evoluciona favorablemente sin complicaciones neurológicas ni digestivas. La histopatología informa teratoma maduro con áreas de neuroepitelio inmaduro, sin atipia celular. DISCUSIÓN: El diagnóstico obstétrico de TSC permite la consejería y derivación oportuna, la planificación quirúrgica, y selección de pacientes que podrían beneficiarse de interrupción precoz, considerando la mortalidad fetal que alcanza 16 por ciento. La clasificación preoperatoria tiene implicancias terapéuticas y pronósticas para estos pacientes. No existe hoy suficiente evidencia de que el tratamiento citotóxico aporte beneficios para teratomas benignos, maduros o inmaduros. En este caso, cabe al seguimiento alejado evaluar las consecuencias del tratamiento, en cuanto a recurrencia, incontinencia urinaria y fecal.

INTRODUCTION: Sacrococcygeal teratoma (SCT) is an uncommon pediatric condition (1 case per 27,000 live births), nevertheless, it is the most frequent neoplasia diagnosed at fetal age. Higher access to obstetric ultrasound allows prenatal diagnosis, appropriate planning, study and multidisciplinary treatment of these patients. CASE REPORT: In a routine obstetric evaluation, patient presented a heterogeneous, cystic mass in the sacrococcygeal region. A SCT was suspected, and an elective cesarean delivery was planned to term gestational age. The patient was delivered without complications, with a 15 cm sacrococcygeal mass. Imaging revealed an Altman II SCT, and serum tumor markers were measured. By the ninth day of life, surgery was performed with tumor and coccyx complete resection, pelvic floor reconstruction and primary closure. Postoperatively, the patient made a good recovery without digestive or neurological complications. The biopsy revealed a mature teratoma with minor immature neuroepithelial foci, without atypical cells. DISCUSSION: The prenatal diagnosis in SCT allows appropriate counseling of parents, derivation to specialized centers, and could identify high-risk patients for early interruption of gestation, taking into account a mortality rate as high as 16 percent. Preoperative classification is important for both treatment and prognosis. There is not enough evidence to recommend chemotherapy for the treatment of mature or immature benign teratomas. In this case, close long-term follow-up will be important to rule out recurrence, and urinary and fecal incontinence.

Quantification of Testosterone (t) by 8 Immunoassays and by Liquid Chromatography -Tandem mass Spectrometry (lc -msms) in Normal and Hirsute Women: A Multicenter Study / Cuantificación de testosterona (t) por 8 inmunoensayos y por cromatografía líquida en tandem con espectrometría de masa (Lc ms/ms): En mujeres normales e hirsutas. Estudio multicéntrico

Objective: To compare T results in normal and hirsute women, obtained by different laboratories employing the same or different methods, including an in-home RIA, and the gold standard method LC-MS/MS. In addition, T results were referred to a curve obtained by 6 different pools that had been prepared on the basis of LC-MS/MS results. Design: Prospective study Setting: Hormone Determination Laboratory, Hospital Italiano, La Plata, and private practice of each participant laboratory. Patient(s): Blood samples were obtained from 78 individuals sorted into 3 groups, namely, normal men (n:39), normal women (n:24) and hirsute women (n:15) Interventions(s): None Main Outcome Measure(s): To evaluate if the results obtained in each lab for each serum sample by the methods currently employed in our country are significantly different from those obtained by LC-MS/MS (Gold standard) Result(s) One out of the 24 NW showed high T values by LC - MS/MS. In each lab, except in 1 (Architect) T results of this serum sample were normal. Two out of the 15 hirsute patients showed normal T values (LC - MS/MS). Method and number of labs -shown between brackets- and percentages of normal T results (false negatives) are described for each method as follows: Chemiluminescence: Axsym - Abbott (Axn) - (3) 85, Architect - Abbott - (Arch); (2) 70; Immulite - Siemmens - (IMM); (2) 42; Electrochemiluminescence - Elecsys - Roche- ((EQL); (4) 52; Fluorescent enzymatic - Vidas - Bio-Merieux - (Vidas) (1) 69; Manual coated tube radioimmunoassay (RIA): RIA - Siemmens Coat-a-Count (RIA S); (3) 64; RIA - DSL Inc (RIA DSL); (1) 31; RIA - DIASource - (DiaS); (1) 31; and in-Home RIA (in-H) (1) 12. Statistically significant differences were obtained between different methods and against LC MS/MS. In-H method is the one that comes closest to 1 on the Weighted Deming regression and closest to zero on the SD intercept, (standard deviation of the constant in the straight line equation) indicating that the values match those obtained by LC - MS/MS. The values recorded by the various methods employed showed no significant modifications when plotted against a secondary standard curve. Conclusion(s) This indicates that the techniques in current use in our area underestimate hyperandrogenemia in these patients. Discrepancies are not due to the various calibration curves proposed in the corresponding commercial kits. The fact that the In-H technique affords finer results while employing a larger serum volume suggests that the disparities among the various commercial methods result from their limited sensitivity to the sample volumes they process. No financial conflicts of interest exist.

El diagnóstico de hiperandrogenemia requiere la demostración de niveles aumentados de Testosterona Total (TT) en suero. Los inmuno ensayos comerciales dan resultados divergentes a niveles bajos de TT como los obtenidos en mujeres. Valoramos los niveles de TT en 24 mujeres normales (MN) y 15 hirsutas (MH) en 18 laboratorios por métodos comúnmente empleados en nuestro medio, Quimioluminiscencia: Axsym - Abbott (Axn)- (3 ), Architect - Abbott - (Arch); (2); Immulite - Siemmens - (IMM); (2); Electroquimioluminiscencia - Elecsys - Roche- ((EQL); (4); Enzimático acoplado a fluorescencia Vidas - Bio-Merieux - (Vidas) (1), Radioinmunoiensayo en tubo recubierto (RIA): RIA - Siemmens (RIA S); (3) 64; RIA - DSL Inc (RIA DSL); (1) 31; RIA - DIASource - (DiaS); (1) 31; y un metodo desarrollado en uno de los laboratorios (in-H) (1).El número entreparéntesis indica elnúmero de laboratorios que emplearon la misma técnica,y comparamos los resultados por LC MS/MS. Comparativamente a LC MS/MS los niveles fueron en todas las muestras significativamente más bajos por AXS y en 18 de las 24 MN por DiaS. En 7 casos; 3 por RIA S, 2 por IMM y 1 por EQL y Arch los valores de TT fueron superiores al límite superior de sus respectivos métodos. En todos los casos se obtuvo una gran variación entre los mismos y con diferentes métodos. Trece de las 15 MH tuvieron niveles altos de TT por LC MS/MS. De las MH con TT aumentada de acuerdo a la determinación por LC MS/MS entre el 12 y el 85 % de las mismas por los distintos métodos fueron normales, indicando que en la mayoría de los métodos habitualmente utilizados en nuestro medio subvaloran la hipernadrogenemia en estas pacientes. Estas diferencias se hacen más notorias a niveles más bajos de TT (Se obtuvieron valores normales en el 71 % de los casos con valores de TT entre 0.47 y 0.74 ng/ml y en el 38 % de los casos, con niveles de TT mayor a 0.98 ng/ml). En 9 muestras se determinó la TT empleando una curva en el rango de 0.21 a 6.44 ng/ml preparada con de una mezcla de 78 sueros cuyos valores fueron obtenidos por LC MS/MS. No se obtuvo una modificación significativa de los valores indicando que la diferencia entre los distintos métodos no es debida a las diferentes curvas de calibración de los kit comerciales. En conclusión ninguno de los métodos mayormente empleados en nuestro medio son aceptables para la evaluación de niveles menores a 1.5 ng/ml.

Relación entre perímetro abdominal, nivel socioeconómico y presión arterial / Relation of abdominal circumference and socio-economic status to blood pressure

Objetivos: Relacionar perímetro abdominal y condición socioeconómica con presión arterial (PA) en comunidad urbana de Concepción. Métodos: Se midió el perímetro abdominal (PeA) de 8472 residentes mayores de 15 años de edad, proporcionados por edad, género y nivel socioeconómico. La PA fue medida con normas estandarizadas, realizando dos visitas en diferentes días, la segunda si la PA era mayor de 140/90 mm Hg. Los Pe A se distribuyeron en cuartiles, relacionando cada cuartil con los respectivos promedios de presión sistólica y diastólica y se establecieron coeficientes de correlación lineal mediante "r" de Pearson entre PeA y PA. Además, se estableció la frecuencia de cada cuartil de Pe A por nivel socioeconómico. Resultados: Los Pea tuvieron la siguiente distribución (cm): 1er cuartil, < 78; 2º cuartil, 78- 87; 3er cuartil, 88-96 y 4º cuartil, > 96. La prevalencia de hipertensión para niveles socioeconómicos alto, medio y bajo fue 17,9 por ciento, 19,5 por ciento y 24,5 por ciento, respectivamente. La PA promedio (mmHg) en hombres y en mujeres del 1er cuartil de PeA fue 112 y 109; en el 2º cuartil 118 y 118; en el 3er cuartil 123 y 122 y en el 4º cuartil 129 y 129, respectivamente. Los coeficientes de correlación entre PeA y presión sistólica y presión diastólica resultaron significativos en ambos géneros: r = 0,343, p<0.00001 y r = 0,281, p<0.00001, respectivamente. La distribución ( por ciento) de PeA fue inversa al nivel socioeconómico: en el nivel social bajo, el 22 por ciento estaba en el 1er cuartil de PeA, y el 28,8 por ciento en el 4º cuartil. En el nivel social alto se observó lo inverso: 38,9 por ciento estaba en el 1er cuartil de PeA, y sólo el 15.5 por ciento en el 4º cuartil (p<0.0001). Conclusiones: Hubo correlación positiva entre PeA y PA en ambos géneros. La frecuencia de mayor PeA en el nivel socioeconómico bajo podría explicar la mayor prevalencia de hipertensión en este grupo.

Aim: To correlate abdominal circumference (AC) and socio-economic status with blood pressure( BP) in an urban community of Concepción, Chile Methods: AC was measured in 8472 subjects above 15years of age, stratified by age, gender and socio-economic status. BP was measured by standard procedures, with a repeat recording when the initial value was > 140/90mmHg. BP was compared in quartiles of abdominal circumference and according to socio-economic status. Pearson "r" was used to correlate BP and AC Results: Cut points for quartiles of AC were 78, 87, and 96 cm. Prevalence of hypertension in high, medium and low socio-economic status was 17.9 percent, 19.5 percent and 24.5 percent, respectively Mean systolic BP was 112 - 109 mmHg (males - females) in the first AC quartile, 118 - 118, 123-122 and 129-129 in the second, third and fourth quartiles, respectively. A significant correlation between AC and BP (systolic and diastolic) was observed in both genders (r 0.345 and 0.281 for males and females, respectively, p<0.00001). 22 percent of low socio-economic subjects belonged in the first AC quartile compared to 28.8 percent in the 4th quartile. In contrast 38.9 percent of high socio-economic subjects belonged in the first AC quartile while 15.5 percent did so in the 4th quartile (p<0001). Conclusion: A positive correlation of AC and blood pressure was shown in both genders. A greater AC in low socio-economic subjects maybe related to a higher prevalence of hypertension in this group.

Rol de la apoptosis en la fisiopatología del lupus eritematoso sistémico / Role of apoptosis in the physiopathology of systemic lupus erythematosus

El Lupus Eritematoso Sistémico (LES) es una enfermedad autoinmune con afectación sistémica, presentando autoanticuerpos y complejos inmunes. En la actualidad existe creciente evidencia acerca del rol de la apoptosis en la fisiopatología del LES. Si la fagocitosis de las células apoptóticas es lenta, puede gatillar fenómenos de autoinmunidad; dicho retraso se ha relacionado con alteraciones de las señales celulares. Además, se ha postulado que la célula apoptótica puede generar procesos autoinmunes a través de la exposición de autoanticuerpos en la superficie de los cuerpos apoptóticos. La tolerogenicidad de la célula apoptótica depende entonces del ambiente, tipo de célula presentadora de antígenos y señales de peligro, pudiendo o no inducir tolerancia. En los modelos de LES se ha demostrado que existen defectos en la apoptosis y en el aclaramiento de las células apoptóticas. Es posible que en el futuro surjan nuevas líneas de investigación en relación a medir la actividad apoptótica, así como el aclaramiento de los cuerpos apoptóticos, con el fin de desarrollarterapias que regulen la apoptosis en los pacientes con LES.

Systemic Lupus Erythematosus (SLE) is a systemic autoimmune disease presenting auto antibodies and immune complexes. There is growing evidence on the role of apoptosis in the physiopathology of SLE. If phagocytosisof apoptotic bodies is slow, due to alterations in surface cell signals, an autoimmune phenomenon may be triggered. Moreover, the apoptotic cell also has the capability of triggering autoimmune diseases by exposing auto antibodies on its surface. The tolerogenic role of the apoptotic cell therefore depends mainly on the environment, type of antigen presenting cell and danger signals, which may either induce or impede tolerance. Defects on apoptosis itself and on the clearance of apoptotic bodies have been demonstrated on SLE models. In the future, new methods of investigation may focus on measuring apoptoticactivity and on apoptotic clearance of apoptotic bodies in order to develop therapies that regulate apoptosis in SLE patients.

Autoevaluación en prácticas clínicas de alumnos del departamento de medicina: carrera de medicina: UMSA gestión 2005-2007 / Self-assessment of students in clinical practice department of medicine carrera de medicina - UMSA management 2005-2007

Objective: To develop a process of self – evaluation in the pre-graduate education during the period of practical work that the students carry out in the different hospital sections and/orin the faculty environment. Research design: Cross sectional design. Location: The study was carried out in the different hospital and faculty sections according to the practical work that the teacher of the Medical School does at the various levels of the third, fourth and fi fth year. Study population:The population of this study were students of the Medical School who did practical work in the 3rd, 4 th and 5th years of the Medical Schools I, II, and III, and by calculation of the sample size for descriptive designs in Epi Info, the result was 180 university students. Due to the feasibility, however, for carrying out this study and in order to increase the power, a total sample of 407 students was used. Methods: The instrument of self – evaluation was applied in the university students after having consulted previously and obtained the acceptance to participate in the study. The method of fi lling out the instrument was explained and fi nally the points of grading were obtained that each student had given himself. Results: The reported results are shown by the answers that were obtained on the qualitative scale for each one of the questions of the applied instrument, and that can be seen according to the order of the questions and their scale inpercentages as can be observed in the fi gures in the text. In the item of preference of key themes as well as in the integration of knowledge in the present specialty, and in the responsible preparation of the activities in the present specialty, the use of adequate resources, demonstration of self- learning abilities like active participation in the practical work and recognition of ways to overcome the weaknesses, they showed a high frequency on the scale of “frequent and...

Pregunta de investigación¿Cuales serán los resultados obtenidos a través de la implementación de un método de auto evaluación en la educación de pregrado en el proceso de prácticas que se realiza en las cátedras de Medicina I, II y III en sus distintos capítulos, durante la gestión 2005 -2006 en la Facultad de Medicina de la UMSA? Objetivo: Desarrollar un proceso de autoevaluación en la educación de pregrado durante el periodo de prácticas que realizan los alumnos en los distintos servicios hospitalarios y/o ambientes facultativos. Diseño de la investigación: Diseño de Corte Transversal. Lugar: Se realiza en los distintos servicios hospitalarios y facultativos de acuerdo al trabajo práctico que realiza el docente de la Carrera de Medicina en los distintos niveles de tercer, cuarto y quinto año. Población: La población de estudio son alumnos de la Carrera de Medicina que realizan prácticas clínicas de 3ro, 4to y 5to de las Cátedras de Medicina I, II y III y por cálculo de tamaño de muestra para diseños descriptivos en Epi Info, resultó 180 estudiantes universitarios, pero por la factibilidad de realizar el estudio y aumentar el poder, se tiene una muestra total de 407 alumnos. Métodos: Se aplicó el instrumento de autoevaluación a los alumnos universitarios previa consulta y confi rmación de aceptación en participar del estudio. Se explicó la forma de llenar el instrumento y fi nalmente se obtuvo la nota de califi cación que ellos mismos se pusieron. Resultados Los resultados reportados se muestran a través de las respuestas obtenidas por la escala cualitativa para cada una de las preguntas del instrumento aplicado, las cuales pueden ser vistas según el orden de las preguntas y su escala en porcentajes, como se observa en las fi guras del texto. En el item de priorización de temas claves...

[Nitric oxide in malignant astrocytes]. / El monóxido de nitrógeno en los astrocitomas malignos.

INTRODUCTION: One of the different molecules involved in the development of astrocytomas is nitric oxide (NO), a gaseous radical that, depending on the cell type and the experimental paradigm selected in the pathology, can play either a cytotoxic or a cytoprotective role. DEVELOPMENT: During the development of an astrocytoma NO acts as a tumouricidal agent, although it can also alter vascular reactivity and lead to neovascularisation, thereby contributing to the invasive capacity (aggressiveness) of the tumour. One of the mechanisms of tumoural progression consists in the protein inactivation resulting from the NO nitration of tyrosine from proteins coded for by tumour-suppressing genes, such as p53. Furthermore, in malignant astrocytes, nitrosoglutathione, a natural NO-donor, has been seen to play a role in the chemoresistance displayed against nitrosourea derivatives. The NO excreted by irradiated astrocytoma cells also appears to be involved in the resistance to the radiotherapy shown by non-irradiated cells. CONCLUSIONS: The molecular mechanisms behind the complex and paradoxical activity of NO in glioblastoma multiforme have still not been fully explained and its implications in vivo are even further from being completely understood.